The model in the K7 pics is not the same one. It has a different registry and is painted differently.
But more important, I must apologize for making a mistake. Buckner sent me lots of photos of the "Bradford" kitbash he built from a Reliant kit and two Saturn V rocket models (which I was able to build a replica of thanks to his generosity in sending the pics to me), but he didn't build the Antares. Those pics were sent to me by someone else, and I mistakenly gave credit to Buckner when I posted the pics at another Trek forum I frequent. I was getting married around that time and simply forgot to make the correction :-(
There were a lot of Reliant model kits (and kitbashes based on them) used for DS9. The 9481 and 4186 Mirandas were just two, while the U.S.S. Trial NCC-1948 was another (although contrary to popular belief, the Trial wasn't used in Way of the Warrior, since the Reliant kit seen in that episode has its rollbar and weapons pod facing the wrong way, so there's yet another model). There was also a four-nacelled Miranda desktop model built from a Reliant kit and nacelles from a TMP Enterprise kit.